Improvement of xylose fermentation in respiratory-deficient xylose-fermenting Saccharomyces cerevisiae
Improvement of xylose fermentation in respiratory-deficient xylose-fermenting Saccharomyces cerevisiae
复制标题
呼吸缺陷型木糖发酵酿酒酵母中木糖发酵的改进
DOI：
10.1016/j.ymben.2011.12.001
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发表时间：
2012-01-01
影响因子：
8.4
通讯作者：
Bao, Xiaoming
中科院分区：
文献类型：
--
作者：
Peng, Bingyin;Shen, Yu;Bao, Xiaoming
木质纤维素中木糖的有效转化有望显著降低第二代生物燃料的生产成本。研究了木糖还原酶-木糖醇脱氢酶（XR-XDH）在酿酒酵母中发酵木糖的影响因素。虽然过量生产的非氧化戊糖磷酸途径显着增加了好氧特定的生长速率木糖和略有改善转化木糖乙醇在氧限制条件下，呼吸的消除删除细胞色素C氧化酶亚基IV基因阻碍好氧生长木糖。然而，具有NADP（+）-偏好XDH突变体的发酵缺陷菌株在木糖培养基中的适应性进化显著地提高了其木糖发酵能力。进化菌株消耗木糖的比生长速率、乙醇产量和木糖醇产量分别为0.06 h-1、0.39 g g（-1）和0.13 g g（-1）。类似于厌氧发酵，进化的菌株表现出积累乙醇，而不是在有氧条件下回收乙醇。(C)2011 Elsevier Inc. All rights reserved.
Effective conversion of xylose in lignocelluloses is expected to reduce the production cost of second-generation biofuels significantly. The factors affecting xylose fermentation in Saccharomyces cerevisiae that express xylose reductase-xylitol dehydrogenase (XR-XDH) are studied. Although overproduction of non-oxidative pentose phosphate pathway significantly increased the aerobic-specific growth rate on xylose and slightly improved conversion of xylose to ethanol under oxygen-limited conditions, the elimination of respiration by deleting cytochrome C oxidase subunit IV gene impeded aerobic growth on xylose. However, the adaptive evolution of the respiratory-deficient strain with an NADP(+)-preferring XDH mutant in xylose media dramatically improved its xylose-fermenting ability. The specific growth rate, ethanol yield, and xylitol yield of the evolved strain on xylose were 0.06 h-1, 0.39 g g(-1), and 0.13 g g(-1) consumed xylose, respectively. Similar to anaerobic fermentation, the evolved strain exhibited accumulated ethanol rather than recycled it under aerobic conditions. (C) 2011 Elsevier Inc. All rights reserved.